This invention relates generally to suction fittings for use with circulating pumps in spas and tubs and, more particularly, to suction fittings as used in combination with pump control devices.
Hot tubs and spas are generally equipped with pumps for the circulation of water. Although some of these pumps are run indefinitely most use a timer for safety reasons, and some use a level sensor to preclude their operation when the water level is low. If a circulating pump were run indefinitely, continuous safe operation would not be assured and possible damage could result. A condition such as low water level could cause the pump to burn out or cause the water jets to spray out of the tub area. A related difficulty is that a person entering or leaving the tub or spa causes undesirable changes in the water level. Too high a level may result in overflow of the tub. Too low a level may uncover the water jets. The use of a timer to control operation of the pump does not adequately address these problems.
Some tubs or spas use a level sensor to control the operation of the pump. A hole is required to be drilled in the wall of these tubs or spas and a fitting installed for connecting an air hose. These fittings increase the chance of leaks by increasing the number of holes in the walls of the tub or spa. These sensors also become inoperative if the hose becomes dislodged.
An important problem with suction fittings arises from blockage of the fitting itself. Foreign objects, such as hair, skin or even a person leaning against the fitting can cause a permanent or temporary blockage, during which the pump will operate unsafely. Blocking the suction fitting with hair or the body can cause serious personal injury or death. While suction fittings are designed to operate safely within a rated flow range, if that flow range is exceeded entrapment can occur. Using a timer or level sensor will not alleviate this problem.
It will be appreciated from the foregoing that there is a need for improvement in the field of suction fittings for water circulation systems. In particular, there is a need for a suction fitting that can operate in conjunction with a pump control device to prevent operation of the pump during unsafe conditions such as blockages. The present invention satisfies this need.